17 year old daughter wants to travel to china from canada, her mother is not in agreement

My daughter lives with myself (father) full time. There is no effective court order regarding custody as one is not required at age 17. We want to travel to PRC and need to know if she can do so with a passport and identification only. Her mother will almost certainly not sign a consent letter. Please indicate what she (or I as her father travelling with her) will need to ensure passage to PRC.
Thank you.